autocycle

Century Dictionary and Cyclopedia

1. n. The trade-name of a combination of two tandem bicycles side by side, between which are the tanks and appliances appropriate to a chemical fire-extinguisher, and a propelling motor. The saddles of the bicycles will carry four men, and the motor will propel the machine at high speed. See also autoquadricycle.
2. n. Same as motor-cycle.

Wiktionary

1. n. A vehicle somewhat like a moped, having a small motor where the pedals would be, and a petrol tank located within the frame.